An array of mooring lines deployed between 300 and 1900 m depth along the Lacaze-Duthiers and Cap de Creus canyons and in the adjacent southern open slope was used to study the water and sediment transport on the western Gulf of Lions margin during the 2006 intense cascading period. Deep-reaching cascading pulses occurred in early January, in late January and from early March to mid-April. Dense water and sediment transport to the deep environments occurred not only through submarine canyons, but also along the southern open slope. During the deep cascading pulses, temporary upper and mid-canyon and open slope deposits were an important source of sediment to the deep margin. Significant sediment *Manuscript Click here to view linked References transport events at the canyon head only occurred in early January because of higher sediment availability on the shelf after the stratified and calm season, and in late February because of the interaction of dense shelf water cascading with a strong E-SE storm. During the January deep cascading pulses, increases in suspended sediment concentration within the canyon were greater and earlier at 1000 m depth than at 300 m depth, whereas during the March-April deep cascading pulses sediment concentration only increased below 300 m depth, indicating resuspension and redistribution of sediments previously deposited at upper and mid-canyon depths. Deeper than 1000 m depth, net fluxes show that most of the suspended sediment left the canyon and flowed along the southern open slope towards the Catalan margin, whereas a small part flowed down-canyon and was exported basinward. Additionally, on the mid-and lower continental slope there was an increase in the near-bottom currents induced by deep open-sea convection processes and the propagation of eddies. This, combined with the arrival of deep cascading pulses, also generated moderate suspended sediment transport events in the deeper slope regions.

Abstract. Settling particles were collected using sediment traps deployed along three transects in the Lacaze-Duthiers and Cap de Creus canyons and the adjacent southern open slope from

During winter 2005–2006, particle fluxes and near‐bottom currents were measured in and around the Lacaze‐Duthiers and Cap de Creus submarine canyons (western Gulf of Lion). Current anomalies show the occurrence of a major dense shelf water cascading event down to the slope, the latest recorded up to date in the area. Concomitant increased total mass fluxes highlight the ability of cascading waters to transport large amounts of coarse sediment and organic matter, which is predominantly of terrestrial origin. In addition, results reveal that the current regime and associated grain size sorting is the responsible for a geochemical gradient of settling organic particles along the slope.

Abstract. Borehole PRGL1-4 drilled in the upper slope of the Gulf of Lion provides an exceptional record to investigate the impact of late Pleistocene orbitally-driven glacioeustatic sea-level oscillations on the sedimentary outbuilding of a river fed continental margin. High-resolution grainsize and geochemical records supported by oxygen isotope chronostratigraphy allow reinterpreting the last 500 ka upper slope seismostratigraphy of the Gulf of Lion. Five main sequences, stacked during the sea-level lowering phases of the last five glacial-interglacial 100-kyr cycles, form the upper stratigraphic outbuilding of the continental margin. The high sensitivity of the grain-size record down the borehole to sealevel oscillations can be explained by the great width of the Gulf of Lion continental shelf. Sea level driven changes in accommodation space over the shelf cyclically modified the depositional mode of the entire margin. PRGL1-4 data also illustrate the imprint of sea-level oscillations at millennial time-scale, as shown for Marine Isotopic Stage 3, and provide unambiguous evidence of relative high sea-levels at the onset of each Dansgaard-Oeschger Greenland warm interstadial. The PRGL1-4 grain-size record represents the first evidence for a one-to-one coupling of millennial time-scale sealevel oscillations associated with each Dansgaard-Oeschger cycle.

Measures of biodiversity change may be useful as indicators if they are responsive to manageable drivers of biodiversity loss. However, there are many candidate indicators that are considered to be robust to survey artifacts and sensitive to manageable impacts. Using extensive survey data on demersal fish assemblages around the Balearic Islands (western Mediterranean) we analyze relationships among 'traditional', taxonomic and functional diversity indices, to identify a minimum set of indices that provide a good representation of the different aspects of diversity. Secondly we model the responses of the demersal fish community diversity to bottom trawl fishing pressure. To do so, we used two different approaches: i) considering fishing effort and depth as continuous explanatory variables; and ii) grouping samples according to bathymetric sampling strata and contrasting levels of fishing effort. The results show that diversity can be described using different complementary aspects such as species richness, evenness, and the taxonomic and functional breadth of the species present in a given community, displaying different responses to fishing pressure. However, the changes in diversity in response to fishing may only be detectable in those communities where the levels of fishing pressure have remained relatively low. When communities have been exposed to high levels of fishing pressure for a long period, the relevant changes in diversity may have happened long before the onset of monitoring of the fishery, and hence it may be too late to detect differences between levels of fishing effort. This seems to be the case on the middle slope of the Balearic Islands, where vulnerable species have disappeared or are very infrequent, and have been replaced by species better-adapted to fishing impacts.

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Borehole PRGL1-4 drilled in the upper slope of the Gulf of Lion provides an exceptional record to investigate the impact of Late Pleistocene orbitally-driven glacio-eustatic sea level oscillations on the sedimentary outbuilding of a river fed continental margin. High-resolution grain-size and geochemical records supported by oxygen isotope chronostratigraphy allow reinterpreting the last 500 ka upper slope seismostratigraphy of the Gulf of Lion which consists of five main sequences stacked during the sea level lowering phases of the last five glacial-interglacial 100-kyr cycles. The high sensitivity to sea level oscillations of the grain-size record along the borehole, favoured by the large width of the Gulf of Lion continental shelf, demonstrates that sea level driven changes in accommodation space over the shelf are able to cyclically modify the depositional mode of the entire margin. PRGL1-4 data also illustrate the imprint of sea level oscillations at millennial scale, as shown for Marine Isotopic Stage 3, and provide unambiguous evidence of relative high sea levels at the onset of each Dansgaard-Oeschger Greenland warm interstadial. The PRGL1-4 grain-size record represents the first evidence ever for a one-to-one coupling of millennial-scale sea level oscillations associated with each Dansgaard-Oeschger cycle